Physical Sciences and Mathematics Commons^™

Drift Detection Using Uncertainty Distribution Divergence, Patrick Lindstrom, Brian Mac Namee, Sarah Jane Delany

Articles

Data generated from naturally occurring processes tends to be non-stationary. For example, seasonal and gradual changes in climate data and sudden changes in financial data. In machine learning the degradation in classifier performance due to such changes in the data is known as concept drift and there are many approaches to detecting and handling it.

Most approaches to detecting concept drift, however, make the assumption that true classes for test examples will be available at no cost shortly after classification and base the detection of concept drift on measures relying on these labels. The high labelling cost in many domains …

Octree-Based Indexing For 3d Point Clouds Within An Oracle Spatial Dbms, Bianca Schoen-Phelan, Abu Saleh Mohammad Mosa, Debra Laefer, Michela Bertolotto

Articles

A large proportion of today’s digital data has a spatial component. The storage and effective 10 management of such data poses particular challenges. Nowhere is this truer than with Light De-11 tection and Ranging (LiDAR), where datasets of even small geographic areas may contain sever-12 al hundred millions points. Currently available spatial information systems do not provide suita-13 ble support for 3D data. As a consequence, while a specific system can be used to store the data, 14 another has to be used to process it. Typically several software applications are used to analyze 15 and process LiDAR data, requiring …

A Viewpoint Of Tanzania E-Commerce And Implementation Barriers, George S. Oreku, Fredrick Mtenzi, Al-Dahoud Ali

Articles

The growing rate of ICT utilization particularly the Internet and mobile phones has influenced at an exponential rate online interaction and communication among the generality of the populace. However, with the enormity of businesses on the Internet, Tanzania is yet to harness the opportunities for optimal financial gains. This study is exploratory in nature as it attempts to unveil the prospects of ecommerce implementation, participation, motivation and opportunity to the developing countries like Tanzania where by the domestic market is very big to ensure the growth of agricultural sector. The paper proposes to investigate the ability of consumers to purchase …

G-Strands And Peakon Collisions On Diff(R), Darryl Holm, Rossen Ivanov

Articles

A G-strand is a map g : R x R --> G for a Lie group G that follows from Hamilton's principle for a certain class of G-invariant Lagrangians. Some G-strands on finite-dimensional groups satisfy 1+1 space-time evolutionary equations that admit soliton solutions as completely integrable Hamiltonian systems. For example, the SO(3)-strand equations may be regarded physically as integrable dynamics for solitons on a continuous spin chain. Previous work has shown that G-strands for diffeomorphisms on the real line possess solutions with singular support (e.g. peakons). This paper studies collisions of such singular solutions of G-strands when G = Diff( …

Mass Transfer From A Vertical Flat Plate Due To A Constant Upward Flow, David Mcdonnell, Brendan Redmond, Lawrence J. Crane

Articles

This paper examines the mass transfer from a vertical flat surface of a soluble material due to a constant upward flow. The mass transfer rate due to this upward flow is calculated and used to obtain the distance along the surface at which the boundary layer separates. For relatively large velocities no separation will occur and the solution approaches that of forced convection on a horizontal surface.

Spectral Multiplicity Of Selfadjoint Schrodinger Operators On Star-Graphs With Standard Interface Conditions, Sergey Simonov, Harald Woracek

Articles

We analyze the singular spectrum of selfadjoint operators which arise from pasting a finite number of boundary relations with a standard interface condition. A model example for this situation is a Schroedinger operator on a star-shaped graph with continuity and Kirchhoff conditions at the interior vertex. We compute the multiplicity of the singular spectrum in terms of the spectral measures of the Weyl functions associated with the single (independently considered) boundary relations. This result is a generalization and refinement of Theorem of I.S. Kac.

Extreme Wave Events In Ireland: 14 680 Bp–2012, Laura Cooke, John M. Dudley, Frédéric Dias

Articles

The island of Ireland is battered by waves from all sides, most ferociously on the west coast as the first port of call for waves travelling across the Atlantic Ocean. However, when discussing ocean events relevant to the nation of Ire- land, one must actually consider its significantly larger designated continental shelf, which is one of the largest seabed territories in Europe. With this expanded definition, it is not surprising that Ireland has been subject to many oceanic events which could be designated as “extreme”; in this paper we present what we believe to be the first catalogue of such …

On The Persistence Properties Of The Cross-Coupled Camassa-Holm System, David Henry, Darryl Holm, Rossen Ivanov

Articles

In this paper we examine the evolution of solutions, that initially have compact support, of a recently-derived system of cross-coupled Camassa-Holm equations. The analytical methods which we employ provide a full picture for the persistence of compact support for the momenta. For solutions of the system itself, the answer is more convoluted, and we determine when the compactness of the support is lost, replaced instead by an exponential decay rate.

Particle Trajectories In Extreme Stokes Waves Over Inifinte Depth, Tony Lyons

Articles

We investigate the velocity field of fluid particles in an extreme water wave over infinite depth. It is shown that the trajectories of the particles within the fluid and along the free surface do not form closed paths over the course of one period, but rather undergo a positive drift in the direction of wave propagation. In addition it is shown that the wave crest cannot form a stagnation point despite the velocity of the fluid being zero there.

Mathematical Modelling At Secondary School: The Macsi-Clongowes Wood College Experience, J.P.F. Charpin, S. O'Hara, Dana Mackey

Articles

In Ireland, to encourage the study of STEM (science, technology, engineering and mathematics) subjects and particularly mathematics, the Mathematics Applications Consortium for Science and Industry (MACSI) and Clongowes Wood College (County Kildare, Ireland) organized a mathematical modelling workshop for senior cycle secondary school students. Participants developed simple mathematical models for everyday life problems with an open-ended answer. The format and content of the workshop are described and feedback from both students and participating teachers is provided. For nearly all participants, this workshop was an enjoyable experience which showed mathematics and other STEM components in a very positive way.

Weyl-Titchmarsh Type Formula For Periodic Schrodinger Operator With Wigner-Von Neumann Potential, Sergey Simonov, Pavel Kurasov

Articles

Schroedinger operator on the half-line with periodic background potential perturbed by a certain potential of Wigner-von Neumann type is considered. The asymptotics of generalized eigenvectors for the values of the spectral parameter from the upper half-plane and on the absolutely continuous spectrum is established. Weyl-Titchmarsh type formula for this operator is proven.

Mass Transfer From A Vertical Flat Plate Due To Natural Convection With A Constant Counterflow, David Mcdonnell, Brendan Redmond, Lawrence J. Crane

Articles

This paper first examines the mass transfer from a vertical flat surface of a soluble material due to natural convection. A perturbation term is then introduced into the stream function to model the introduction of a constant counterflow. The effect this counterflow has on both the overall mass transfer and the overall velocity profile is studied in detail.

Bayesian Model Selection For Exponential Random Graph Models, Alberto Caimo, Nial Friel

Articles

Exponential random graph models are a class of widely used exponential family models for social networks. The topological structure of an observed network is modelled by the relative prevalence of a set of local sub-graph configurations termed network statistics. One of the key tasks in the application of these models is which network statistics to include in the model. This can be thought of as statistical model selection problem. This is a very challenging problem---the posterior distribution for each model is often termed ``doubly intractable'' since computation of the likelihood is rarely available, but also, the evidence of the posterior …

Endomorphisms Of Abelian Groups With Small Algebraic Entropy, D. Dikranjan, Ketao Gong, P. Zanardo

Articles

We study the endomorphisms ϕ of abelian groups G having a “small” algebraic entropy h (where “small” usually means ). Using essentially elementary tools from linear algebra, we show that this study can be carried out in the group , where an automorphism ϕ with must have all eigenvalues in the open circle of radius 2, centered at 0 and ϕ must leave invariant a lattice in , i.e., be essentially an automorphism of . In particular, all eigenvalues of an automorphism ϕ with must be roots of unity. This is a particular case of a more general fact known …

Ultrasound For Improved Crystallisation In Food Processing, N. Misra, Navneet Deora, Brijesh Tiwari, Patrick J. Cullen

Articles

Within the food industry, controlling crystallisation is a key factor governing food structure, texture and consumer appeal, with some foods requiring the promotion of crystallisation in a controlled manner (e.g. chocolate) and others a check (e.g. in honey). Sonocrystallisation is the application of ultrasound energy to control the nucleation of a crystallisation process. The use of power ultrasound provides a non-invasive approach to producing crystals with desired properties. Sonocrystallisation facilitates process control, primarily by modulating crystal size distribution and morphology. This paper details the governing mechanisms of sonocrystallisation. Proven and potential applications of the process in foods, including chocolates, honey, …

Eigenfunction Expansions Associated With The One-Dimensional Schrödinger Operator, Daphne Gilbert

Articles

We consider the form of eigenfunction expansions associated with the time-independent Schrödinger operator on the line, under the assumption that the limit point case holds at both of the infinite endpoints. It is well known that in this situation the multiplicity of the operator may be one or two, depending on properties of the potential function. Moreover, for values of the spectral parameter in the upper half complex plane, there exist Weyl solutions associated with the restrictions of the operator to the negative and positive half-lines respectively, together with corresponding Titchmarsh-Weyl functions.

Synthesis And Modification Of Octafluoro[2.2]Paracyclophane (Parylene Af4), Craig Hicks, Brendan Duffy, Gráinne Hargaden

Articles

Parylenes are a class of organic compounds which have gained significant attention due to their application as coatings in areas such as medical devices and electronics. This review highlights the development of synthetic pathways to Octafluoro[2.2]Paracyclophane, commonly referred to as parylene AF4. Methods which have been used to functionalise AF4 are also presented.

One Step Quick Detection Of Cancer Cell Surface Marker By Integrated Nife-Based Magnetic Biosensing Cell Cultural Chip, Chenchen Bao, Lei Chen, Tao Wang, Daxiang Cui, Chong Lei, Yong Zhou, Furong Tian

Articles

RGD peptides has been used to detect cell surface integrin and direct clinical effective therapeutic drug selection. Herein we report that a quick one step detection of cell surface marker that was realized by a specially designed NiFe-based magnetic biosensing cell chip combined with functionalized magnetic nanoparti- cles. Magnetic nanoparticles with 20-30 nm in diameter were prepared by coprecipitation and modified with RGD-4C, and the resultant RGD-functionalized magnetic nanoparticles were used for targeting cancer cells cul- tured on the NiFe-based magnetic biosensing chip and distinguish the amount of cell surface receptor-integrin. Cell lines such as Calu3, Hela, A549, CaFbr, HEK293 …

A Comparison Of Three Commercially Available Contrast-Detail Phantoms And Evaluation Of The Contrast-Detail Performance Under A Range Of Instrument Settings, Jacinta Browne, Des Hickey, Ashling Mcnabb

Articles

No abstract provided.

Sol-Gel Characteristics For Corrosion Resistance Of Anodised Aluminium, Michael Whelan, John Cassidy, Brendan Duffy

Articles

Conventional anodising electrolytes based on sulphuric acid, oxalic acid and phosphoric acid have been used to form nanoporous layers on AA3003-H14 and sealed with silane based sol-gel sealers. It is shown that the sol-gel chemistries have varying levels of pore penetration depending on the synthesis conditions. The extent of sol-gel penetration and pore sealing is analysed by electron microscopy and energy dispersive x-ray spectroscopy. To describe the sealing phenomena observed a sol-gel penetration and sealing rating has been proposed to explain the interactions of the sol-gels with the pores of the anodised layers. The corrosion resistance of the sol-gel sealed …

Novel Microwave Assisted Synthesis Of Zns Nanomaterials, Suresh Pillai, Michael Seery, Damian Synnott, John Colreavy, Stephen Hinder

Articles

A novel ambient pressure microwave-assisted technique is developed in which silver and indium modified ZnS is synthesised. The as prepared ZnS is characterised by X-ray diffraction, UV-Vis spectroscopy, X-ray photoelectron spectroscopy and luminescence spectroscopy. This procedure produced crystalline materials with particle sizes below 10 nm. The synthesis technique leads to defects in the crystal which induce mid energy levels in the band gap and lead to indoor light photocatalytic activity. Increasing the amount of silver causes a phase transition from cubic blende to hexagonal phase ZnS. In a comparative study, when the ZnS cubic blende is heated in a conventional …

A Comparison Of Raman, Ftir And Atr-Ftir Micro Spectroscopy For Imaging Human Skin Tissue Sections., Syed Mehmood Ali, Franck Bonnier, Helen Lambkin, Kathleen Flynn, V Mcdonagh, Claragh Healy, T C. Lee, Fiona Lyng, Hugh Byrne

Articles

Raman and Infrared absorption spectroscopies are compared for the analysis of human hand skin tissue sections. The tissue sections have been formalin fixed and paraffin processed, and subsequently dewaxed. Fourier Transform infrared (FTIR) spectra are preprocessed using the resonant Mie – extended multiplicative scattering algorithm to remove spectral artefacts. FTIR images of resolution 4cm^-1, analysed using K-means cluster analysis, reveal the double layer structure of the dermis and epidermis, but no further layer differentiation is achieved using the higher spatial resolution of the Attenuated Total Reflection imaging or improved spectral resolution of 2cm^-1. At comparable spectral …

Raman Spectroscopy In Nanomedicine: Current Status And Future Perspectives, Hugh Byrne, Mark Keating

Articles

Raman spectroscopy is a branch of vibration spectroscopy which is capable of probing the chemical composition of materials. Recent advances in Raman microscopy have added significantly to the range of applications which now extend from medical diagnostics to exploring interfaces between biological organisms and nanomaterials. In this review, Raman is introduced in a general context, highlighting some of the areas in which the technique has found success in the past, as well as some of the potential benefits it offers over other analytical modalities. The subset of Raman techniques which specifically probe the nanoscale, namely Surface Enhanced and Tip Enhanced …

Raman Micro Spectroscopy Study Of The Interaction Of Vincristine With A549 Cells Supported By Expression Analysis Of Bcl-2 Protein, Haq Nawaz, Amaya Garcia, Aidan Meade, Fiona Lyng, Hugh Byrne

Articles

Understanding the interaction of anticancer drugs with model cell lines is important to elucidate the mode of action of these drugs as well as to develop cost effective and rapid screening methods. Raman spectroscopy has been demonstrated to be a valuable technique for high throughput, noninvasive analysis. The interaction of vincristine with a human lung adenocarcinoma cell line (A549)was investigated using Raman micro spectroscopy. The results were correlated with parallel measurements from the MTT cytotoxicity assay, which yielded an IC₅₀ value of 0.10 ± 0.03 μM. The Raman spectral data acquired from vincristine treated A549 cells was analysed to …

The Bio-Nano-Interface In Predicting Nanoparticle Fate And Behaviour In Living Organisms: Towards Grouping And Categorising Nanomaterials And Ensuring Nanosafety By Design, Hugh Byrne, Arti Ahluwalia, Diana Boraschi,, Bengt Fadeel, Peter Gehr, Arno C. Gutleb, Michaela Kendall, Manthos Papadopoulos, Iseult Lynch

Articles

In biological media, nanoparticles acquire a coating of biomolecules (proteins, lipids, polysaccharides) from their surroundings, which reduces their surface energy and confers a biological identity to the particles. This adsorbed layer is the interface between the nanomaterial and living systems and therefore plays a significant role in determining the fate and behaviour of the nanoparticles. This review summarises the state of the art in terms of understanding the bio-nano interface and provides direction for potential future research directions and some recommendations for future priorities and strategies to support the safe implementation of nanotechnologies. The central premise is that nanomaterials must …

Required Features Of A Virtual Classroom Tool For Use In Higher Education, Arnold Hensman

Articles

The integration of virtual-classroom systems into the arsenal of e-learning tools represents a major evolution in the landscape of modern distance education. For many courses, standard virtual learning environments (VLEs) provide only a foundation upon which to base a distance learning programme. However, synchronous live online-teaching software such as Microsoft Office Communicator and Adobe Connect allow educators to simulate a real-time classroom environment over the internet like never before. Since these tools are being used more and more within higher education, questions must be asked about how effective they ultimately can be in meeting student learning requirements. More importantly, what …

Dark Solitons Of The Qiao's Hierarchy, Rossen Ivanov, Tony Lyons

Articles

We obtain a class of soliton solutions of the integrable hierarchy which has been put forward in a series of works by Z. Qiao. The soliton solutions are in the class of real functions approaching constant value fast enough at infinity, the so-called 'dark solitons'.

G-Strands, Darryl Holm, Rossen Ivanov, James Percival

Articles

A G-strand is a map g(t,s): RxR --> G for a Lie group G that follows from Hamilton's principle for a certain class of G-invariant Lagrangians. The SO(3)-strand is the G-strand version of the rigid body equation and it may be regarded physically as a continuous spin chain. Here, SO(3)_K-strand dynamics for ellipsoidal rotations is derived as an Euler-Poincar'e system for a certain class of variations and recast as a Lie-Poisson system for coadjoint flow with the same Hamiltonian structure as for a perfect complex fluid. For a special Hamiltonian, the SO(3) …

Spectral Cross Correlation As A Supervised Approach For The Analysis Of Complex Raman Datasets: The Case Of Nanoparticles In Biological Cells, Mark Keating, Franck Bonnier, Hugh Byrne

Articles

Spectral Cross-correlation is introduced as a methodology to identify the presence and subcellular distribution of nanoparticles in cells. Raman microscopy is employed to spectroscopically image biological cells previously exposed to polystyrene nanoparticles, as a model for the study of nano-bio interactions. The limitations of previously deployed strategies of K-means clustering analysis and principal component analysis are discussed and a novel methodology of Spectral Cross Correlation Analysis is introduced and compared with the performance of Classical Least Squares Analysis, in both unsupervised and supervised modes. The previous study demonstrated the feasibility of using Raman spectroscopy to map cells and identify polystyrene …

Nitrogen And Copper Doped Solar Light Active Tio2 Photocatalysts For Water Decontamination, Mike Fisher, Donal Keane, Pilar Fernandez-Ibanez, John Colreavy, Stephen Hinder, Kevin Mcguigan, Suresh Pillai

Articles

A novel class of photocatalytic coating capable of degrading bacterial and chemical contaminants in the presence of visible sunlight wavelengths was produced by depositing a stable photocatalytic TiO

2 film on the internal lumen of glass bottles via a sol–gel method. This coating was prepared in either undoped form or doped with nitrogen and/or copper to produce visible light-active TiO2 films which were annealed at 600 ◦C and were characterized by Raman and X-ray photoelectron spectroscopy. The presence of doped and undoped TiO2 films was found to accelerate the degradation of methylene blue in the presence of natural sunlight, while …